Catheter apparatus with telescoping lumen catheters and its use in methods for treating vasculatures

ABSTRACT

The invention provides for methods and catheter apparatus for passing one or more guidewires (via the use of one or more telescoping guidewire lumens) through a chronic total occlusion of a vasculature. The catheter apparatus may include: a catheter shaft having a distal end; one or more telescoping guidewire lumen catheters passing longitudinally through the shaft, wherein the one or more guidewire lumen catheters are capable of telescoping beyond the distal end of the catheter shaft; an expansible distal portion of the shaft; and a retractable sheath covering at least a portion of the expansible distal portion of the shaft, wherein retracting the retractable sheath from the expansible distal portion of the shaft directly activates the expansible distal portion of the shaft causing expansion of the expansible distal portion of the shaft.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/842,744, filed Mar. 15, 2013, which is a continuation-in-partapplication of U.S. application Ser. No. 13/166,623, filed Jun. 22, 2011(now U.S. Pat. No. 8,764,730 (issued Jul. 1, 2014)), which is adivisional application of U.S. patent application Ser. No. 12/147,130,filed Jun. 26, 2008 (now U.S. Pat. No. 7,988,646 (issued Aug. 2, 2011)),which claims priority to U.S. Provisional Application No. 60/929,395,filed Jun. 26, 2007, U.S. Provisional Application No. 60/960,900, filedOct. 19, 2007, U.S. Provisional Application No. 60/996,057, filed Oct.26, 2007, and U.S. Provisional Application No. 61/064,715, filed Mar.21, 2008, the contents of which are incorporated by reference herein intheir entireties. This application also claims priority to U.S.provisional application No. 61/716,856, filed Oct. 22, 2012, thecontents of which are incorporated by reference in its entirety.

FIELD OF THE INVENTION

The invention relates generally to apparatus and methods for treatingvasculatures, and, more particularly, to methods and apparatus forpassing one or more guidewires through a chronic total occlusion of avasculature via the use of a catheter apparatus configured to containone or more telescoping lumen catheters.

BACKGROUND OF THE INVENTION

A chronic total occlusion in a coronary artery, peripheral artery, vein,dialysis fistula, or other types of vasculature represents a challengefor percutaneous treatment. Percutaneous treatments are generallypreferred revascularization options as compared to bypass surgery.Continuing improvements in equipment specifically developed for chronictotal occlusions have allowed success rates to improve. Although thesuccess rates for these types of procedures have improved, theprocedures for percutaneous treatments still suffer from severaldrawbacks. Patients without a successful percutaneous treatment may needto undergo bypass surgery or experience continuing symptoms from theocclusions.

A major obstacle within a chronic total occlusion may often beencountered while attempting to advance a guidewire across the chronictotal occlusion in a vasculature. A maximum resistance may be met at themost proximal point of the lesion, i.e. the firm, fibrous cap. Whilebeing advanced, a guidewire may tend to deflect away from the fibrouscap towards the adventitial layer, often entering a false lumen. Thisoff-axis displacement of the guidewire often may result in a proceduralfailure.

Successful passage of the guidewire may also be obstructed by randomlylocated calcified regions of atherosclerotic plaque within the mass ofthe lesion. Microchannels within the obstruction may be desirabletargets for the tip of the guidewire. However, these soft spots withinthe lesion are difficult to identify angiographically and are dispersedrandomly within the matrix of the lesion.

Coronary arteries and other vasculatures tend to be non-linear conduits,often coursing over the surface of the epicardium and other tissues. Thesuccess of current technology is limited by this type of geometry. Incurrent systems, a guidewire or currently available catheter is advanceddown a vasculature to the level of the obstruction. At the point of theobstruction, the guidewire advancement may tend to proceed along theouter, greater curvature of the vasculature. Even a guidewire centeredwithin the vasculature at the proximal edge of the chronic totalocclusion may tend to proceed toward the outer, greater curvature of avasculature.

As a result, only a minor portion of the surface area of the obstructionmay be encountered with sufficient force to allow passage of theguidewire. On many occasions, the angle of encounter and/or the forceapplied to the fibrous cap may not be sufficient for crossing thefibrous cap with the guidewire. If the tip of the guidewire is curvedprior to placement through the support catheter, direct longitudinalforce may be compromised as the wire is advanced off axis. If a rapidexchange catheter system is used as catheter support, the guidewire maybuckle within the guide-catheter resulting in suboptimal longitudinalguidewire force.

At times, a single lumen angioplasty balloon may be inflated justproximal to the chronic total occlusion in an attempt to center theguidewire in the vessel lumen and provide additional support for theguidewire. Atherosclerotic lesions tend to be asymmetric with aneccentric true lumen. Therefore, attempts to limit the guidewire to thecentral axis of the vessel lumen may result in lower rates of proceduralsuccess.

Generally, needs exist for improved apparatus and methods for treatingvasculatures. More specifically, needs exist for improved apparatus andmethods for efficiently and effectively passing a guidewire through achronic total occlusion in a vasculature.

SUMMARY OF THE INVENTION

Embodiments of the present invention solve many of the problems and/orovercome many of the drawbacks and disadvantages of the prior art byproviding an apparatus and method for treating vasculatures.

In particular, embodiments of the invention may accomplish this with anapparatus for efficiently and effectively passing a guidewire through achronic total occlusion in a vasculature. The apparatus may have aflexible shaft having a distal end, one or more guidewire lumens havinga distal end and passing longitudinally through the shaft, and apositioning means for positioning distal ends of the one or moreguidewires relative to an inner wall of an external lumen. The apparatusmay have one or more lumen catheters (such as e.g. 3), which may bejointly or independently movable such that the distal end of the one ormore lumen catheters telescopes beyond the distal end of the flexibleshaft. The one or more lumen catheters may also be jointly or separately(i.e. independently) operable. An actuator may control the operation ofsuch lumen catheters. The lumen catheters are configured for passage ofa guidewire.

The positioning means may be an expansible scaffold initially in anon-expanded state. A retractable sheath may surround the expansiblescaffold and the retractable sheath may be retracted for expanding theexpansible scaffold.

The positioning means may also be one or more balloons where the one ormore balloons are inflated through an inflation port runninglongitudinally in the shaft. The positioning means may also includeguidewire lumens coupled to or otherwise disposed within the expansiblescaffold. The positioning means may also include inflatable meanssurrounding distal ends of the guidewire lumens. The inflatable meansmay or may not be located within an expansible scaffold.

The positioning means may also be a rotatable core within the shaft. Thepositioning means may also include a deflectable tip on the catheter.The positioning means may also include a shape-memory materialintegrated with the guidewire lumens.

A method of operating a catheter apparatus may include providing acatheter apparatus including a flexible shaft, one or more guidewirelumens passing longitudinally through the shaft, one or more guidewireswithin the one or more guidewire lumens, and a positioning means,inserting a guide catheter into a vasculature with a chronic totalocclusion, inserting the catheter apparatus into the guide catheter,activating the positioning means for positioning the one or moreguidewires relative to the chronic total occlusion, and advancing theone or more guidewires through the one or more guidewire lumens and intocontact with the chronic total occlusion.

The one or more guidewires may be passed through the chronic totalocclusion. The catheter apparatus may be withdrawn from the vasculaturewhile leaving the one or more guidewires in place. The one or moreguidewires may be withdrawn from contact with the chronic totalocclusion and the one or more guidewires may be advanced through the oneor more guidewire lumens into contact with the chronic total occlusionrepeatedly until a suitable site for passing the one or more guidewiresthrough the chronic total occlusion is found. The positioning means maybe activated before each advancing of the one or more guidewires throughthe one or more guidewire lumens into contact with the chronic totalocclusion.

Another embodiment of the present invention may be a catheter apparatusincluding a multi-lumen main shaft; one or more guidewire lumensextending from a distal end of the multi-lumen shaft with lumens withinthe one or more guidewire lumens contiguous with at least one of themulti-lumens of the multi-lumen main shaft; an expansible supportstructure coupled to the distal end of the multi-lumen shaft; one ormore loops corresponding to each of the one or more guidewire lumens,wherein the one or more loops corresponding to each of the one or moreguidewire lumens are coupled to the expansible support structure, andwherein the one or more loops corresponding to each of the one or moreguidewire lumens project inward from the plane of the expansible supportstructure; and wherein the one or more guidewire lumens are threadedthrough the corresponding one or more loops.

Another embodiment of the invention is a catheter apparatus including: amain catheter shaft; one or more lumen telescoping catheters, each lumencatheter configured for passing over one or more guidewire; each lumencatheter capable of telescoping in and out from a distal end of the maincatheter shaft; and an expansible support structure coupled to thedistal end of the main catheter shaft, the expansible support structureconfigured so that each telescoping lumen microcatheter can telescope inand out of the expansible support structure. The main catheter shaft mayhave one or more telescoping lumen catheter shafts. The one or moretelescoping lumen catheters may pass through the one or more telescopinglumen catheter shafts. The telescoping lumen catheters may be coupled tothe expansible support structure. The expansible support structure maybe self-expanding and it may be a scaffold.

The expansible support structure may be capable of surrounding the oneor more telescoping lumen catheters. When the expansible supportstructure (e.g. scaffold) surrounds the one or more lumen catheters, theexpansible support structure has one or more inward facing loops eachcorresponding to one or more of the telescoping lumen catheters andwherein each of the one or more telescoping lumen catheters are threadedthrough the corresponding one or more loops. These one or more inwardfacing loops may be coupled to the expansible support structure by loopconnections. The expansible support structure may include closed cells.These closed cells, for example, may be approximately hexagonal withexpansible S-shaped connectors on two opposing sides of the hexagon. Theexpansible support structure may be made from a shape memory alloy suchas e.g. nitinol.

The apparatus may also include a retractable sheath covering at least aportion of the expansible support structure of the main catheter shaft,wherein retracting the sheath from the distal portion of the shaftdirectly activates the expansible support structure. The retractablesheath may be advanced around the expansible support structure tocompress the expansible support structure. In addition, the apparatusmay include an actuator. Operation of the actuator may control movementof the one or more telescoping lumen catheters.

The one or more telescoping lumen catheters may be capable of separatelytelescoping in and out of the main catheter shaft. For example, onetelescoping lumen catheter may be capable of separately telescoping inand out of the main catheter shaft. Alternatively, two or moretelescoping lumen catheters may be capable of separately telescoping inand out of the main catheter shaft. In one embodiment, the one or moretelescoping lumen catheters surround the main catheter shaft and thedistal tip of each of the one or more telescoping lumen catheters iscoupled to the support structure.

Another embodiment of the invention is a catheter apparatus including ashaft having a proximal and a distal end; one or more telescoping lumencatheters surrounding the shaft, each telescoping lumen catheterconfigured for passing over one or more guidewires; each telescopinglumen catheter capable of telescoping the distal end the main cathetershaft; an support structure coupled to the distal end of the shaft,wherein the distal end of each lumen catheter is coupled to thescaffold. The coupling may be on the interior of the support structure(e.g. scaffold). The support structure may be self-expansible. Theexpansible support structure may be capable of surrounding the one ormore telescoping lumen catheters. When the support structure surroundsthe lumen catheters, the structure has one or more inward facing loopscorresponding to each corresponding to one or more the telescoping lumencatheters and wherein each of the one or more telescoping lumencatheters are threaded through the corresponding one or more loops. Theone or more inward facing loops may be coupled to the expansible supportstructure by loop connections. The expansible support structure mayinclude closed cells which are approximately hexagonal with expansibleS-shaped connectors on two opposing sides of the hexagon. Apparatus mayalso include a retractable sheath covering at least a portion of theexpansible support structure of the main catheter shaft, whereinretracting the sheath from the distal portion of the shaft directlyactivates the expansible support structure.

Another embodiment of the invention is a method for advancing aguidewire through an obstructed vasculature including: inserting thecatheter apparatus having a main shaft and one or more telescoping lumencatheter is passing, each telescoping lumen catheter configured forpassing over one or more guidewires into an obstructed vasculature;expanding an expansible support structure on the distal end of the mainshaft; telescoping one or more telescoping lumen catheters in and out ofmain catheter shaft and through the expanded support structure; andadvancing one or more guidewires through the one or more telescopinglumen catheters and into contact with an obstruction. The main cathetershaft may have one or more telescoping lumen catheter shafts throughwhich one or more telescoping lumen catheters is passing. The one ormore telescoping lumen catheters may telescope individually. The one ormore telescoping lumen catheters may provide support to the one or moreguidewires.

The support structure may be a scaffold. The support structure may alsobe made from a shape memory alloy such as e.g. nitinol. The supportstructure may also be made of a self-expanding. When the supportstructure is self-expanding, the step of expanding the expansiblesupport structure includes withdrawing a sheath surrounding the supportstructure. The expansible support structure may surround the one or moretelescoping lumen catheters and may have one or more inward facing loopscorresponding to each corresponding to one or more the telescoping lumencatheters and wherein each of the one or more telescoping lumencatheters are threaded through the corresponding one or more loops.

The step of telescoping may include telescoping the telescoping lumencatheters out of the main catheter until resistance is felt. The methodmay also include sequentially advancing the one or more telescopinglumen catheters. The step of telescoping may further include measuringthe distance a telescoping lumen catheter advances and the method mayalso further include advancing the one or more guidewire through thetelescoping lumen catheter that advances the furthest.

Additional features, advantages, and embodiments of the invention areset forth or apparent from consideration of the following detaileddescription, drawings, and claims. Moreover, it is to be understood thatboth the foregoing summary of the invention and the following detaileddescription are exemplary and intended to provide further explanationwithout limiting the scope of the invention as claimed.

BRIEF DESCRIPTION OF THE INVENTION

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate preferred embodiments of theinvention and together with the detailed description serve to explainthe principles of the invention. In the drawings:

FIG. 1A is a perspective view of a self-expanding catheter apparatus.

FIG. 1B is a distal end view of the catheter apparatus of FIG. 1A.

FIG. 1C is a cross section view of a midpoint of the catheter apparatusof FIG. 1A.

FIG. 1D is a perspective view of the self-expanding end of the catheterapparatus of FIG. 1A in an expanded state with a stop point.

FIG. 1E is a cross section view of a midpoint of the catheter apparatusof FIG. 1D.

FIG. 1F is distal end view of the catheter apparatus of FIG. 1D.

FIG. 1G is a perspective view of the self-expanding end of the catheterapparatus of FIG. 1A in an expanded state with a truncated conicalportion.

FIG. 1H is a side view of the catheter apparatus of FIG. 1A in asheathed state.

FIG. 1I is a perspective view of the catheter apparatus of FIG. 1A witha deflectable tip.

FIG. 1J is a side view of a shorter constraining sheath.

FIG. 1K is a side view of a longer constraining sheath.

FIG. 2A is a perspective view of a catheter apparatus with a singleballoon.

FIG. 2B is a cross section view of a midpoint of the catheter apparatusof FIG. 2A.

FIG. 3A is a perspective view of a catheter apparatus with doubleballoons.

FIG. 3B is a cross section view of a midpoint of the catheter apparatusof FIG. 3A.

FIG. 4A is a perspective view of a catheter apparatus with a balloon.

FIG. 4B is a distal end view of the catheter apparatus of FIG. 4A.

FIG. 4C is a cross section view of a midpoint of the catheter apparatusof FIG. 4A.

FIG. 5A is a perspective view a catheter apparatus with a rotating innercore.

FIG. 5B is a cross section view of a midpoint of the catheter apparatusof FIG. 5A.

FIG. 6A is a perspective view a catheter apparatus with a deflecting tipand stabilizing balloon.

FIG. 6B is a cross section view of a midpoint of the catheter apparatusof FIG. 6A.

FIG. 7A is a perspective view of a catheter apparatus with an expansiblemesh tip.

FIG. 7B is a detail of the catheter apparatus of FIG. 7A.

FIG. 8A is a perspective view of a catheter apparatus with guidewirelumens coupled to an expansible mesh tip.

FIG. 8B is a detail of the catheter apparatus of FIG. 8A.

FIG. 8C illustrates the retraction of a retractable sheath from thecatheter apparatus of FIG. 8A and FIG. 8B.

FIG. 8D illustrates the retraction of a retractable sheath as in FIG. 8Cwithin a vasculature.

FIG. 9A is a perspective view of a catheter apparatus with expandabledevices surrounding the lumen guidewires.

FIG. 9B illustrates the retraction of a retractable sheath from thecatheter apparatus of FIG. 9A.

FIG. 10 illustrates the retraction of a retractable sheath from acatheter apparatus with shape-memory materials integrated with guidewirelumens.

FIG. 11 illustrates the retraction of a retractable sheath from acatheter apparatus and expansion of sponges surrounding guidewirelumens.

FIG. 12A is a perspective view of a loop embodiment in an expandedstate.

FIG. 12B is an unwrapped view of the loop embodiment of FIG. 12A.

FIG. 12C is a distal end view of the loop embodiment of FIG. 12A.

FIG. 13 is an unwrapped view of another loop embodiment where loops maybe located on any closed cell.

FIG. 14A to 14E show a schematic view of a catheter having telescopinglumen catheters.

FIG. 15 A to FIG. 15C show a distal end view of a catheter havingtelescoping lumen catheters.

FIG. 16A to FIG. 16C show another embodiment of a catheter havingtelescoping lumen catheters.

FIG. 17A is a perspective view of a loop embodiment in an expandedstate.

FIG. 17B is an unwrapped view of the loop embodiment of FIG. 17A.

FIG. 18A to FIG. 18C show another embodiment of a catheter apparatus inaccordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention may include apparatus and methodsfor advancing one or more guidewires through an obstructed vasculaturessuch as e.g. chronic total occlusions (CTOs) in vasculatures. Thesupport and centering functionality has application beyond CTOs, eventhough the preferred embodiments described herein are directed tosupport and centering to facilitate a guidewire to cross through a CTO.

Embodiments of the present invention may incorporate several features tosuccessfully pass one or more guidewires through an obstructedvasculature such as e.g. a chronic total occlusion. Features of thepresent invention may include multiple lumens constructed within acatheter shaft, expansion, or activation of a distal tip of a catheterapparatus for creating a scaffold effect, and/or decentralization of theguidewire lumens after activation or distal catheter repositioning forallowing multiple sections of a fibrous cap to be forcefully engaged bya guidewire. Features of the present invention may further include oneor more lumen catheters that may be independently (separately) orjointly movable and, therefore, be advanceable beyond the distal end ofthe catheter shaft. For example, the multiple lumen catheters may betelescoping beyond the distal end of the catheter shaft. Embodiments ofthe present invention may optimize advancement of the one or moreguidewires into multiple sections of a fibrous cap of a chronic totalocclusion with reasonable force.

In embodiments of the present invention, one or more over-the-wirelumens may be constructed within a shaft of a catheter apparatus.Embodiments of the present invention may preferably use two or morelumens such as e.g. three lumens. The lumen may be configured toaccommodate lumen catheters. The lumen catheters may be independentlyadvanceable. The lumen catheters may be advanceable so that the lumencatheters may extend (e.g. telescope) beyond the shaft of the catheterapparatus. In addition, the lumen catheters may retract into the shaftof the catheter apparatus. Larger vasculatures, such as coronaryarteries, may accommodate higher profile catheters and allow use ofadditional lumens. Each lumen may accommodate at least a 0.014″ diameterguidewire. Other sized lumens and guidewires may be accommodated basedupon the desired end use. Standard off-the-shelf or customizedguidewires may be used. For example, in addition to traditionalguidewires, embodiments of the present invention may be used withguidewires including, but not limited to, steerable, hydrophilic,Teflon-coated, heparin-coated, ball-tip, J-tip, spiral tip, angulatedwire and others.

Embodiments of the present invention may be combined with other types ofcatheter devices. The positioning systems and methods of the presentinvention may be to deliver and/or direct other catheters towards adesired position. For example, a vibrating catheter or other specializedcatheter may be directed towards a chronic total occlusion or otherlocation in a vasculature. A microcatheter with a distal positioningdevice, including, for example, one or more balloons that may beinflated individually, sequentially or simultaneously, or otherfeatures, may be placed in proximity to a chronic total occlusion. Apositioning system may steer the microcatheter away from a wall of avessel, as it probes a cap of a chronic total occlusion. Microcatheterswith angulation or other features may be placed in proximity to achronic total occlusion where the angulation steers away from a wall ofa vessel, probes a cap of a chronic total occlusion or otherwise changesdirections. A catheter portion and/or sheath of embodiments of thepresent invention may be large enough to deliver and/or positionspecialized catheters to a desired location. Positioning devices maythen be used to position the specialized catheters in a beneficialmanner for a procedure.

In particular, embodiments of the present invention may deliver energyvia the guidewires through radio frequencies and/or lasers. Furthermore,other types of energy may be delivered such as direct conductive heatenergy, infrared or other types of energy that may be useful inparticular applications. Various types of guidewires and/or deliveringenergy via guidewires may allow for various types of treatments. Theexternal diameter of a catheter apparatus of the present invention mayallow passage through a standard guide catheter. The outer surface of acatheter apparatus of the present invention may be coated withhydrophilic material to allow easier passage through the guide catheter.With alternate dimensions, the catheter apparatus of the presentinvention may be used in peripheral vessels. In this situation, a guidecatheter may not be necessary to insert the device into the vasculature.

FIGS. 1A-1K show a self-expanding catheter apparatus 11. The externaldiameter of the self-expanding catheter apparatus 11 may pass through asheath 19.

The sheath 19 may be a separate element surrounding the distal end ofthe catheter apparatus 11 to maintain the catheter apparatus 11 in aninactive state. The sheath 19 may have a rounded or tapered end forfacilitating passage through a vasculature. Other end configurations arepossible depending on particular uses.

Additional embodiments of the sheath may be shown in FIGS. 1J-1K. Asheath 68, 69 may be used to lower a profile of a self-expanding distalportion 13 of the catheter apparatus 11, which may preferably be anitinol component, during insertion and removal of the catheterapparatus 11 from a vasculature. A sheath 68 may have a shorterconfiguration, as shown in FIG. 1J, covering at least a distalself-expanding component, preferably a nitinol element, on the catheterapparatus 11. The sheath 68, however, may preferably be long enough tocorrespond to the length of the treated vasculature, i.e., long enoughto cover the portion of the catheter extending outside of a guidecatheter and into the vasculature. This sheath configuration mayfunction by insertion through a guide catheter and advancement into atreated vasculature. The sheath 68 may be attached 60 to a solid coreguidewire and/or flexible device 67. The solid core guidewire and/orflexible device 67 may be long enough to traverse a guide catheter. Thesolid core guidewire and/or flexible device 67 may be a solid structurewith no internal lumens and may preferably be made of plastic or similarmaterials. The solid core guidewire and/or flexible device 67 may bemanipulated from outside the body, preferably by means of an expandedelement 64 at a proximal end of the solid core guidewire and/or flexibledevice 67. The solid core element 67 may parallel the catheter apparatus11 through a guide catheter. A distal portion 58 of the sheath 68 may beflared to fit a self-expanding portion 13 of the catheter apparatusdevice 11. The distal portion 58 may also have one or more radiopaque orother types of markers 54. The sheath 68 may have a stop point to allowwithdrawal of the sheath 68 to a predetermined position, which may alsofacilitate resheathing of the catheter apparatus 11.

Alternatively, as shown in FIG. 1K, a sheath 69 may have a longerlength, completely surrounding an intravascular portion of the catheterapparatus 11 during insertion and removal. The sheath 69 may be aflexible with a roughly cylindrical shape. The sheath 69 may preferablybe made of plastic or other similar materials. This sheath configurationmay have a larger profile element 62 at an extra-vascular, proximal end,allowing for easier handling and movement of the sheath 69. A distalportion 66 of the sheath 69 may be flared to fit a self-expandingportion 13 of the catheter apparatus device 11. The distal portion 66may also have one or more radiopaque or other types of markers 56. Thesheath 69 may have a stop point to allow withdrawal of the sheath 69 toa predetermined position, which may also facilitate resheathing of thecatheter apparatus 11. The sheath 69 may be used in conjunction with aguide catheter or may function without a guide catheter in anon-coronary vasculature.

A body or shaft 23 of the catheter apparatus 11 may be made of aflexible plastic material or any other similar substance. A hydrophiliccoating may or may not be added to the outer surfaces of the catheterapparatus 11. One or more hubs 21 corresponding to one or moreguidewires 15 and one or more lumens 17 may be disposed at a proximateend 29 of the catheter apparatus 11.

The one or more hubs 21 may be marked, color-coded, numbered or mayotherwise differentiate between one another. Identification ofindividual guidewire lumens may allow more effective use of embodimentsof the present invention. With marking, users may improve their abilityto identify which guidewire lumen may be preferably used during aprocedure. For example, if a particular guidewire lumen is in apreferable location relative to other guidewire lumens an operator maydesire a quick and reliable method of inserting a guidewire through thatparticular guidewire lumen. Marking may save time and effort byeliminating trial and error to determine a desired guidewire lumen.Alternatively, marking may be useful for applications other thantreatment of occluded vasculatures, such as steering guidewires throughvasculatures via various lumens. For example, marking can allowembodiments of the present invention to be used in other areas and/orconditions of a vasculature, such as traversing the tortuous coronaryarteries. Distal and proximal ends of the guidewire lumens may besimilarly marked to identify the guidewire lumens. Distal ends orstructures on distal ends of the guidewire lumens may be marked suchthat the user may identify a preferred guidewire lumen while thecatheter apparatus is within a patient. Marking with radiopaque or othertypes of markers may include temporary structures within the guidewirelumens. For example, markers may be present on stylets within theguidewire lumens. The stylets may be removed if desired to reduce massor otherwise improve efficiency of a procedure.

The one or more hubs 21 may allow introduction of stylets or otherstructures that run through the catheter apparatus to render it stiff orto remove debris from its lumen. The one or more hubs 21 may also allowpassage of one or more guidewires 15.

Generally, a distal portion 13 of the catheter apparatus 11 may functionas a scaffold-type structure. The distal portion 13 of the catheterapparatus 11 may stabilize the catheter apparatus 11 within avasculature lumen as one or more guidewires 15 are advanced into achronic total occlusion. One or more guidewires 15 may be threadedthrough one or more lumens 17 within the catheter apparatus 11. Thedistal portion 13 of the catheter apparatus 11 is preferablyself-expanding. FIG. 1B shows the distal end 25 of the catheterapparatus 11 in an expanded state. FIG. 1C shows a cross section of thecatheter apparatus 11 with a retractable sheath 19 surrounding the body23. The retractable sheath 19 may be retracted by moving the retractablesheath towards the proximate end 29 of the catheter apparatus 11. Thedistal portion 13 of the catheter apparatus 11 may include an activatedscaffold structure 27 to stabilize the catheter apparatus 11. Theactivated scaffold structure 27 may expand to match a diameter of thevasculature lumen upon retraction of the retractable sheath 19.

Nitinol and/or stainless steel may be incorporated into the scaffoldstructure 27. Nitinol is an illustrative example of a shape memoryalloy. Other shape memory alloys or other similar substances may beused. Generally, after a sample of a shape memory alloy has beendeformed from its original crystallographic configuration, the shapememory alloy regains its original geometry by itself. This property ofshape memory alloys may allow for expansion of the scaffold structure 27after retraction of the retractable sheath 19. The nitinol and/orstainless steel scaffold structure 27 may create a stent-like mesh. Thescaffold structure 27 may form the surface of the distal portion 13 ofthe catheter apparatus 11.

FIG. 1H shows an inactive scaffold structure 31. The inactive scaffoldstructure 31 may be advanced over a guidewire into a chronic totalocclusion with a retractable sheath 19 in place to constrain theself-expanding but inactive scaffold structure 31. The retractablesheath 19 may cover the inactive scaffold structure 31. When theinactive scaffold structure 31 is properly positioned, the retractablesheath 19 may be retracted by an appropriate retraction means. As theretractable sheath 19 is retracted, the inactive scaffold structure 31of the catheter apparatus 11 may become active and may flare out. Duringa flare out process, the inactive scaffold structure 31 may self-expandto assume a larger diameter to roughly approximate the diameter of thevasculature in the location of the distal portion 13 of the catheterapparatus 11.

The refraction of the retractable sheath 19 may be a continuous orstep-wise process. For example, the retractable sheath 19 may beretracted in one operation by a user until the scaffold structure 31 isfully exposed. Alternatively, the retractable sheath 19 may be retractedin increments less than that required for full expansion of the scaffoldstructure 31. Stop points during retraction of the retractable sheath 19may allow for predetermined quantities of expansion of the scaffoldstructure 31. For example, if a procedure required less than fullexpansion of the scaffold structure 31, a stop point short of fullretraction of the retractable sheath 19 may be chosen.

The conversion and expansion of the inactive scaffold structure 31 intoan active scaffold structure 27 may create a relatively stable platformfrom which to advance the one or more guidewires 15 into multiplesections of the chronic total occlusion. The activated catheterapparatus 11 with the retractable sheath 19 retracted may have anactivated scaffold structure shaped as a truncated cone or othersuitable shape. A surface 33 of the expanded distal end 13 of thecatheter apparatus 11 may consist of a “skin” of the scaffold structure27. An end cap 35 may or may not cover the distal end 35 of the catheterapparatus 11. The end cap 35 may preferably be made of an imperviousexpandable polymer, but other similar substances may be used.

FIG. 1D shows an activated scaffold structure 27 that may be filled withan expandable polymer or similar material. The expandable polymer orsimilar material may fill the scaffold structure 27 to form a truncated,conical or other appropriate shape for securing the catheter apparatus11 within the vasculature lumen. The expandable polymer may supportdistal portions of one or more guidewire lumens 17. Upon expansion ofthe expandable polymer, the embedded lumen ends 37 may flare outcorrespondingly with the end cap 35. FIG. 1E shows a cross section ofthe catheter apparatus 11 with the retractable sheath 19 surrounding theshaft 23. FIG. 1F shows an end view of the expanded end cap 35 withembedded guidewire lumens 17.

A skin 33 may surround the expandable polymer or similar material. Theskin 33 may be a temporary metal “stent.” The metal stent may be a meshtype structure. The metal stent may become a truncated conical shapeafter expansion or any other suitable shapes.

The a-b dimension 39 indicated in FIG. 1D may shorten when theretractable sheath 19 is removed from scaffold structure 27. The degreeof shortening of the a-b dimension 39 may vary depending on the degreeof expansion, the materials used, etc.

The retractable sheath 19 may be refracted to a stop point. The stoppoint may prevent over-retraction of the retractable sheath 19. Aretractable sheath 19 at the stop point may facilitate re-sheathing ofthe scaffold structure 27.

FIG. 1G shows multiple guidewire lumens 17 that may be suspended withina scaffold structure 27 without using an expansible polymer or similarfiller. A skin 33 may be made of nitinol, stainless steel, or anotherexpansible substance. The one or more guidewire lumens 17 may extend tothe distal end 25 of the scaffold structure 27. The scaffold structure27 may begin roughly at a transition point 41. The one or more guidewirelumens 17 may or may not be embedded in an end cap 35. The end cap mayan impervious plastic material.

FIG. 1I shows a catheter apparatus with an expandable skin 33 and adeflectable tip 43. The deflectable tip 43 may be rotatable or otherwisemoveable. The deflectable tip 43 may be rotatable with a rotator 45 orother similar device at the proximate end 29 of the catheter apparatus11. The embodiment depicted in FIG. 1I preferably does not include andend cap 35. The lack of an end cap 35 may allow for freedom of movementof the deflectable tip 43. The distal portion 13 of the catheterapparatus 11 may flare after the retractable sheath 19 is retracted. Asingle, centrally located deflectable lumen 47 may allow a guidewire 15to be advanced in numerous planes. The deflectable tip 43 may allow forcontrolled probing of the fibrous cap of a chronic total occlusion.

Other embodiments of the present invention may include one or moreballoons at or near a distal end of a catheter apparatus. The one ormore balloons may be circumferential. Alternatively, the one or moreballoons may be offset and placed longitudinally. Other positions andarrangements are possible depending on particular situations.

FIG. 2A shows an embodiment of the present invention with a balloon 53that may be placed longitudinally near a distal tip 55 of a catheterapparatus 51. The balloon 53 may parallel the long axis of a shaft 59 ofthe catheter apparatus 51. Inflation of the balloon 53 may deflect theposition of one or more guidewire lumens 57 relative to the fibrous capof a chronic total occlusion. The balloon 53 may be inflated to adiameter that may buttress the catheter apparatus 51 against a wall ofthe vasculature lumen. The balloon 53 may then be deflated, the catheterapparatus 51 rotated, and the balloon 53 re-inflated.

FIG. 2B shows a cross section of the catheter apparatus 51. The balloon53 may be inflated and deflated through an inflation port 65. Theinflation port 65 may pass through the shaft 59 to connect the balloon53 to a proximate end 63 of the catheter apparatus 51. This method mayresult in one or more guidewires 59 probing various sections of thefibrous cap. One or more hubs 61 at the proximate end 63 of the catheterapparatus 51 may allow passage of the one or more guidewires 59. Styletsor other similar structures may be inserted or reinserted into thecatheter apparatus 51 to facilitate rotation.

FIG. 3A shows an embodiment of the present invention with a firstlongitudinal balloon 73 and a second longitudinal balloon 75 positionednear a distal end 77 of a catheter apparatus 71. More balloons may beused for additional or different control of the catheter apparatus. Themultiple balloons 73, 75 may be inflated individually, simultaneously,alternatively or sequentially depending on the particular circumstances.The pattern of inflation and/or deflation of the multiple balloons 73,75 may allow redirection of a distal catheter tip 79 relative to afibrous cap of a chronic total occlusion. Repositioning of the distalcatheter tip 79 may permit more complete interrogation of the fibrouscap with one or more guidewires 81. One or more hubs 83 at the proximateend 85 of the catheter apparatus 71 may allow passage of the one or moreguidewires 81 through a shaft 87.

FIG. 3B shows a cross section of the catheter apparatus 71. One or moreguidewire lumens 89 may pass through the catheter apparatus 71.Embodiments of the present invention may be constructed with multipleinflation ports (not shown) or with one inflation port 91 servicing themultiple balloons 73, 75. If the latter option is utilized, the balloonmaterials may be constructed to allow selective, and/or sequentialinflations at increasing balloon pressures. The balloons 73, 75 may bepositioned at various angles relative to one another around thecircumference of the shaft 87.

FIG. 4A shows an embodiment of the present invention with a balloon 103with a distal surface 105 in a catheter apparatus 101. The balloon 103may be flat, cylindrical, or any other suitable configuration.Additionally, the balloon 103 may be sectioned. One or more guidewirelumens 107 may be extruded through the balloon material. The balloon 103may be inflated to match the inner diameter of the vasculature lumen.FIG. 4B shows an end view of the catheter apparatus 101. As the balloon103 expands, the one or more guidewire lumens 107 extruded through theballoon 103 may diverge relative to one another in reaction to expansionof the balloon 103. The divergence may allow one or more guidewires 109to probe various sections of the fibrous cap of the chronic totalocclusion. One or more hubs 111 at the proximate end 113 of the catheterapparatus 101 may allow passage of the one or more guidewires 109. FIG.4C shows a cross section of the catheter apparatus 101. A ballooninflation port 115 may pass through a shaft 117 with the one or morelumens 107 to inflate and/or deflate the balloon 103.

FIG. 5A shows a catheter apparatus 121 with an inner core 123 within anouter core 125. The inner core 123 may contain one or more lumens 127.Embodiments of the present invention may preferably include two or morelumens 127. FIG. 5B illustrates an embodiment with two lumens placed atpositions of 3 o'clock and 9 o'clock within the inner core 123. Otherquantities of lumens 127 and positions are contemplated for variousapplications and situations. The inner core 123 may be rotated withinthe outer shell 125 of the catheter apparatus 121 by turning orotherwise manipulating a rotator 129 at a proximate end 131 of thecatheter apparatus 121. The rotator 129 may be coupled 133 or otherwiseconnected to the inner core 123. One or more guidewires 135 may beconnected to one or more hubs 137 at the proximate end 131 of thecatheter apparatus 121. The one or more guidewires may extend from adistal end 139 of the catheter apparatus 121.

A rotatable inner core 123 of catheter apparatus 121 may be used inconjunction with the various balloon configurations described above. Forexample, if constructed with a non-longitudinal stabilizing balloon, theshape of the distal tip balloon may be circumferential, i.e.,doughnut-shaped.

FIG. 6A shows an embodiment of the present invention with a singlestabilizing balloon 143 and a deflecting tip 145 on a catheter apparatus141. The single stabilizing balloon 143 may be used in conjunction witha deflectable distal catheter tip 145 for eccentric placement of one ormore guidewires 147. The one or more guidewires 147 may be passedthrough one or more hubs 149 at a proximate end 151 of the catheterapparatus 141. FIG. 6B shows a cross section of the catheter apparatus141. One or more lumens 153 may pass through a shaft 155. An inflationport 157 may allow inflation and/or deflation of the stabilizing balloon143. The deflecting tip 145 may be located at various angles dependingon the particular situation.

Catheter apparatus shafts 23, 59, 87, 117, 12, and 155 may beconstructed with either a circular, oval, or rectangular shape. Othershapes are possible depending on particular uses.

FIG. 7A shows an embodiment of the present invention with an expansibleportion 159 at a distal tip 161 of a catheter apparatus 163. Theexpansible portion 159 may be a mesh or other similar configuration asdescribed above. The expansible portion 159 may be expanded byretracting a retracting sheath 165 away from the distal tip 161 of thecatheter apparatus 163. The expansible portion 159 may be expanded intocontact with a wall of a vasculature.

FIG. 7B shows a detail of the catheter apparatus 163. A central core 167may contain one or more guidewire lumens 169. The central core 167 mayor may not be expandable. The central core 167 may be rotatable to allowone or more guidewires 169 to probe various sections of a fibrous cap.One or more hubs 171 at the proximate end 173 of the catheter apparatus163 may allow passage of the one or more guidewires 169.

FIG. 8A shows an embodiment of the present invention with an expansibleportion 175 at a distal tip 177 of a catheter apparatus 179. Theexpansible portion 175 may be a mesh or other similar configuration asdescribed above. The expansible portion 175 may be expanded byretracting a retracting sheath 181 away from the distal tip 177 of thecatheter apparatus 179. The expansible portion 175 may be expanded intocontact with a wall of a vasculature. One or more hubs 185 at theproximate end 187 of the catheter apparatus 179 may allow passage of theone or more guidewires 189.

FIG. 8B shows a detail of the catheter apparatus 179. One or moreguidewire lumens 183 may be formed of extruded plastic or similarmaterials. The figures generally illustrate three guidewire lumens 183,but other numbers and configurations may be desirable depending onparticular uses. The one or more guidewire lumens 183 may haveshape-memory alloys or other similar materials integrated into,surrounding or within the structure of the one or more guidewire lumens183. Preferably, the one or more guidewire lumens 183 may self-expandupon retraction of the retraction sheath 181 such that ends 182 of theone or more guidewire lumens are spaced apart and approximately halfwaybetween the center point and the inner surface of a vasculature. The oneor more guidewire lumens 183 may be configured to expand into variouspredetermined positions and configurations depending on particularapplications. For example, FIG. 8B shows a triangular configuration forthe guidewire lumens 183. Other configurations are possible using threeguidewire lumens 183. Furthermore, different numbers of guidewire lumensmay be used in various configurations.

Alternatively, the one or more guidewire lumens 183 may be coupled to aninner surface of the expansible portion 175. The one or more guidewirelumens 183 may be adhered or integrally molded to the inner surface ofthe expansible portion 175.

Expansion of the expansible portion 175 may cause the one or moreguidewire lumens 183 to separate via a self-expanding shape-memorymaterial. Alternatively, the one or more guidewire lumens 183 may not becoupled to the expansible portion 175 but may instead be positionedwithin the internal volume of the expansible section 175 to allowprobing of a fibrous cap. Additionally, a self-expanding polymer mayfill the expansible portion 175. In an initial configuration theself-expanding polymer may be in a compressed state. As the expansibleportion 175 is released from the retracting sheath 181, theself-expanding polymer may expand as well. The one or more guidewirelumens 183 may be embedded in the self-expanding polymer and may bemoved into a desired position by the expansion of the self-expandingpolymer. The self-expanding polymer may expand by absorbing moisture orblood from within the vasculature or through other expansion mechanisms.The self-expanding polymer may then be removed after a procedure.

FIG. 8C illustrates the operation of the catheter apparatus 179 of FIG.8A and FIG. 8B. Similar operational procedures may be used for otherembodiments described herein. Step 1 of FIG. 8C shows the catheterapparatus 179 in an initial state with a retractable outside sheath 181moved as far as possible distally from a guidewire lumen tube 191. Steps2-7 show incremental stages of retraction of the retractable outsidesheath 181. As the retractable outside sheath 181 is retracted back overthe guidewire lumen tube 191, the expansible portion 175 isincrementally exposed and allowed to expand. As the expansible portion175 expands the one or more guidewire lumens 183 separate and are heldin a desired position by the shape-memory alloy materials or by couplingto the expansible portion 175. Step 7 shows the expansible portion 175in a fully deployed state. The end view of FIG. 8C shows the one or moreguidewire lumens 183 in the fully deployed state. Step 8 shows aguidewire 189 inserted through a guidewire lumen 183. FIG. 8Dillustrates the operation of the catheter apparatus 179 as shown in FIG.8C within a vasculature 184 with an occlusion 186.

FIG. 9A shows an embodiment of the present invention with one or moreinflatable devices 193 surrounding one or more guidewire lumens 195within an expansible portion 197 of a catheter apparatus 199. Theexpansible portion 197 may be a mesh or other similar configuration asdescribed above. The expansible portion 197 may be expanded byretracting a retracting sheath 201 away from a distal tip 203 of thecatheter apparatus 199. The expansible portion 197 may be expanded intocontact with a wall of a vasculature. The expansible portion 197 may beomitted as shown in FIG. 9B.

The inflatable devices 193 may initially be in a deflated conditionduring insertion and positioning of the catheter. The inflatable devices193 preferably are balloons, but may be any other expansible type ofdevice. The balloons may surround the outer surface of the one or moreguidewire lumens 195. The balloons may be cylindrical or other shapes toposition the one or more guidewire lumens 195 within the expansibleportion 175. The inflatable devices 193 may include one balloon for eachguidewire lumen 195 or one balloon may correspond to several guidewirelumens 195. For example, a single inflatable device 193 may be inflatedto separate all of the guidewire lumens 195. Alternatively, two separateinflatable devices 193 may be used to separate three or more guidewirelumens. The inflatable devices 193 may be bifurcated or trifurcateddepending on the number of guidewire lumens 195 and the particularapplication. The expansible sheath 197 may assist in containingmultiple, separate inflatable devices 193, but may not be essential tothe operation of the present invention.

One or more ports (not shown) may allow inflation or one or more of theinflatable devices 193 depending on the number of separate inflatabledevices 193. For example, one port may be used to inflate one inflatabledevice 193. Alternatively, if two or more separate inflatable devices193 are present, then two or more ports may be used to inflate anddeflate the inflatable devices 193 serially or in parallel depending ona particular use or condition. Different numbers and combinations ofinflatable devices and ports may be possible. Inflation of variouscombinations of inflatable devices 193 with various numbers andconfigurations of ports may allow for probing of a fibrous cap. If endsof the one or more guidewire lumens 195 or the inflatable devices 193themselves are marked, a user may inflate specific inflatable devices193 but not others to more accurately interrogate an occlusion. Each ofthe inflatable devices 193 may be inflated into contact with theexpanded expansible portion 197 to secure the position of the one ormore guidewire lumens 195. Guidewires (not shown) may then be passedthrough the one or more guidewire lumens 195. The inflatable devices 193may be deflated prior to withdrawing the catheter apparatus 199.

As shown in FIG. 9B an embodiment of the present invention may includethe inflatable devices 193 without the expansible portion 197, as shownin FIG. 9A. The inflatable devices 193 may be exposed by withdrawing theretracting sheath 201. Particularly if the inflatable devices 193 areunitary, the expansible portion 197 may not be needed. However, even ifthe inflatable devices 193 are separate the expansible portion 197 maybe omitted.

Step 1 of FIG. 9B shows the catheter apparatus 199 in an initial statewith a retractable outside sheath 201 moved as far as possible distallyfrom a guidewire lumen tube 205. Steps 2-4 show incremental stages ofretraction of the retractable outside sheath 201 to expose the one ormore guidewire lumens 195 with corresponding inflatable devices 193.Steps 5-6 show incremental stages of inflation of the inflatable devices193 into a final position with a vasculature 209 with an occlusion 211.Step 7 shows the catheter apparatus 199 in a fully deployed state. Step8 shows a guidewire 207 inserted through a guidewire lumen 195.

FIG. 10 illustrates operation of a catheter apparatus 213 that mayinclude shape-memory materials integrated with the one or more guidewirelumens 217. Preferably, the one or more guidewire lumens 217 may beconstructed out of extruded plastic or other similar materials.Shape-memory or other expansible materials may be integrated into,surround, be contained within or reinforce the one or more guidewirelumens 217.

Step 1 of FIG. 10 shows the catheter apparatus 213 in an initial statewith a retractable outside sheath 215 moved as far as possible distallyfrom a guidewire lumen tube 215. The one or more guidewire lumens 217may be exposed by withdrawing the retracting sheath 215 from the distalend of a catheter apparatus 213 as shown in Steps 2-6. The one or moreguidewire lumens 217 may then assume a final spaced or relaxedconfiguration as shown in Step 7. The guidewire lumens may move outwardrelative to one another a desired distance and/or into contact withinner walls of a vasculature 219 with an occlusion 221. A guidewire 223may then be threaded through the one or more guidewire lumens 217 asshown in Step 8. After completion of a procedure, the retracting sheath215 may be advanced towards the distal end of the catheter apparatus tocompress the one or more guidewire lumens 217 into a compact arrangementfor removal from the vasculature 219. Alternatively, the one or moreguidewire lumens 217 may be withdrawn into the distal end of theretracting sheath 215 before removal from the vasculature 219.

FIG. 11 illustrates operation of a catheter apparatus 225 withexpansible devices 227 surrounding one or more guidewire lumens 229.Preferably, the expansible devices 227 are sponges or other materialsthat expand within the vasculature without input from a user. Eachguidewire lumen 229 may have a separate expansible device 227 ormultiple guidewire lumens may be incorporated into one expansible device227.

Step 1 of FIG. 11 shows the catheter apparatus 225 in an initial statewith a retractable outside sheath 231 moved as far as possible distallyfrom a guidewire lumen tube 233. The one or more guidewire lumens 229may be exposed by withdrawing the retracting sheath 231 from the distalend of a catheter apparatus 225 as shown in Steps 2-6. As the retractingsheath 231 is withdrawn from the expansible devices 227, the expansibledevices 227 begin to expand. If the expansible devices 227 are sponges,the expansible devices 227 may absorb moisture from the vasculature toincrease in volume. The one or more guidewire lumens 229 may then assumea final expanded configuration as shown in Step 7. The guidewire lumens229 embedded with the expansible devices 227 may move outward relativeto one another a desired distance and/or into contact with inner wallsof a vasculature 233 with an occlusion 235. A guidewire 237 may then bethreaded through the one or more guidewire lumens 229 as shown in Step8. After completion of a procedure, the retracting sheath 231 may beadvanced towards the distal end of the catheter apparatus 225 tocompress the one or more guidewire lumens 229 into a compact arrangementfor removal from the vasculature 233. Alternatively, the one or moreguidewire lumens 229 may be withdrawn into the distal end of theretracting sheath 231 before removal from the vasculature 233. Movementof the retracting sheath 231 may compress the expansible devices 227into a position suitable for removal from the vasculature 233. If theexpansible devices 227 are sponges, the compression may force moistureout of the sponges.

Generally, after crossing a chronic total occlusion with a guidewire,the catheter apparatus may be resheathed and removed from thevasculature. The guidewire may be left in position.

One or more guidewires preferably remain in or near the longitudinalaxis of the corresponding support catheter lumen. This positioning ofthe one or more guidewires may optimize the force of the one or moreguidewires when engaged with the fibrous cap of the chronic totalocclusion. Multiple eccentrically located guidewire lumens may improvethe chance of success in passing one or more guidewires through achronic total occlusion. The mass of the multi-lumen support cathetermay provide additional support for the guidewire and prevents off-axis,i.e., lateral, displacement of portions of the one or more guidewireslocated in the guide catheter and in the vasculature. Eccentricdistribution of the one or more guidewire lumens may allow engagement ofmultiple, eccentric sections of the fibrous cap. Embodiments of thepresent invention may permit simultaneous placement of multipleguidewires. Multiple guidewires may enhance available techniques such as“parallel guidewire” and “see-saw” wire.

FIG. 12A shows a catheter apparatus 241 with guidewire lumens 243, 245,247 passing through loops 249, 251, 253, 255, 257, 259. The number andconfiguration of the loops or guidewire lumens 243, 245, 247 may bevariable. Alternative numbers and configurations are possible. Guidewirelumens 243, 245, 247 may be guided into a predetermined position duringexpansion of an expansible support structure 261 by threading theguidewire lumens 243, 245, 247 through the inwardly projecting loops249, 251, 253, 255, 257, 259. Loops 249, 251, 253, 255, 257, 259 may becoupled to the expansible support structure 261. FIGS. 12A-12Cillustrate an embodiment of the present invention where each guidewirelumen 243, 245, 247 may pass through two loops 249, 251, 253, 255, 257,259. Alternative embodiments may only use one loop for each guidewirelumen. Still other alternative embodiments may use three or more loopsfor each guidewire lumen. The operation of the loops and guidewirelumens in FIGS. 12A-12C are illustrative of the alternative embodiments.The guidewire lumens 243, 245, 247 are guided into position by passingthrough the loops 249, 251, 253, 255, 257, 259. The expansible supportstructure 261 may be coupled to a main multi-lumen shaft 263 by anyconventional means such as adhesive, welding, etc. In the currentembodiment of the invention, three guidewire lumens 243, 245, 247 areshown, but other numbers and configurations of lumens may be provided. Asheath 265 may hold the expansible support structure 261 in a compressedstate prior to deployment of the expansible support structure 261.

FIG. 12B shows a flat projection of the expansible support structure 261with loops 249, 251, 253, 255, 257, 259. FIGS. 12A-12C show a fiveclosed-cell configuration. Embodiments of the present invention mayinclude different quantities of closed-cells depending on desiredapplications. FIG. 12B shows a first closed cell 265, a first connectorregion 267, a second closed cell 269, a second connector region 271, athird closed cell 273, a third connector region 275, a fourth closedcell 277, a fourth connector region 279, and a fifth closed cell 281. InFIG. 12B, the first closed cell 265 may be at a distal end of thecatheter apparatus 241 and the fifth closed cell 281 may located towardsa proximal end of the catheter apparatus 241. In each closed cell,struts 283 may form a zigzag pattern to support the catheter apparatus241. Connectors 285 residing in the first connector region 267 mayconnect the first closed cell 265 to the second closed cell 269 bylinking strut intersections 287 on the first closed cell 267 with strutintersections 289 on the second closed cell 271. Connectors 285 may bethinner than struts 283 and the angular relationship between struts 283and connectors 285 may change during expansion and compression of theexpansible support structure 261. Similar structures and interactionsmay be found in and between the remaining closed cells.

Loops 249, 251, 253, 255, 257, 259 may be located at strut intersections291. Loops 249, 251, 253, 255, 257, 259 may be coupled to the strutintersections 291 by loop supports 293. Loop supports 293 may be taperedto reduce stress on the apparatus. Struts 283 may also be tapered toreduce stress on the apparatus. The loop supports 293 may be positionedat other locations along the struts 283 or connectors 285 if desired.Loops 249, 251, 253, 255, 257, 259 and inner shape cutouts may becircular, oval, oblong or any additional shapes to allow the guidewirelumens 243, 245, 247 to slide within the loops 249, 251, 253, 255, 257,259. Shapes other than circles may be beneficial when the loops 249,251, 253, 255, 257, 259 lie at an angle other than perpendicular to thecylindrical plane of the expansible support structure 261. Loops 249,251, 253, 255, 257, 259 may be shaped to correspond to guidewire lumens243, 245, 247 and allow the guidewire lumens 243, 245, 247 to slidethrough the loop openings.

Each guidewire lumen 243, 245, 247 may pass through two loops in theembodiment of FIGS. 12A-12C. For example, guidewire lumen 243 may passthrough loops 249 and 251, guidewire lumen 245 may pass through loops253 and 255, and guidewire lumen 247 may pass through loops 257 and 259.Passing the guidewire lumens 243, 245, 247 through the loops 249, 251,253, 255, 257, 259 may position the guidewire lumens 243, 245, 247 in adesired position within the expansible support structure 261. Asindicated above, other numbers and configurations of loops are possible.To prevent twisting and damage to the guidewire lumens 243, 245, 247,the loops 249, 251, 253, 255, 257, 259 for each guidewire lumen arepreferably located on every other closed cell. As shown in FIG. 12B, theloops 249, 251, 253, 255, 257, 259 are located on the first closed cell265 and the third closed cell 273. The loops 249, 251, 253, 255, 257,259 may also be located on, for example, the second closed cell 269 andthe fourth closed cell 277. If additional loops are present, then theloops may be located on closed cells separated by one closed cell. Thisalternating structure may prevent twisting during expansion andcompression of the expansible support structure 261 that may damage ormisalign the guidewire lumens 243, 245, 247. Preferably, no loops 249,251, 253, 255, 257, 259 may be located on the fifth or proximal closedcell 281. The fifth closed cell 281 may be adhered to the main tri-lumenshaft 263. Thus, the fifth closed cell 281 may not fully expand duringexpansion of the expansible support structure 261 and may not beappropriate for holding loops 249, 251, 253, 255, 257, 259. Similarly,the fourth closed cell 277 may not fully expand and may also not besuitable for holding loops.

The expansible support structure 261, the guidewire lumens 243, 245,247, and the loops 249, 251, 253, 255, 257, 259 may initially be in acompressed state within a sheath 265 as described in previousembodiments. The sheath 265 may hold the expansible support structure261 in a compressed state. The sheath 265 may include a radiopaquemarker at a distal end of the sheath 265 or another known location alongthe sheath 265. The radiopaque marker may provide an indication of howmuch of the expansible support structure 261 is covered by the sheath265. This may allow for partial withdrawal of the sheath 265.

The expansible support structure 261 may be made of nitinol or anothershape-memory material. The loop connectors 293 may also be made ofnitinol or another shape-memory material. The loop connectors 293 may beset to project inwardly from the cylindrical plane of the expansiblesupport structure 261 at a given angle. The angle may be any angle, butis preferably approximately 30 degrees inward from the cylindricalplane. The angle or the length of the loop connectors 293 or both may bevaried to create various positions of the guidewire lumens 243, 245, 247within the expansible support structure 261. The loops 249, 251corresponding to a guidewire lumen 243 may project in oppositedirections, for example, loop 249 may project in a distal direction, andloop 251 may project in a proximal direction.

When the sheath 265 is withdrawn from around the expansible supportstructure 261, the expansible support structure 261 may expand to anexpanded state. The sheath 265 may be partially or completely withdrawnfrom the expansible support structure 261. During expansion of theexpansible support structure 261, the loops 249, 251, 253, 255, 257, 259may project inward from the cylindrical plane of the expansible supportstructure 261 to hold the guidewire lumens 243, 245, 247 in apredetermined position within the expansible support structure 261. Theguidewire lumens 243, 245, 247 may remain within the loops 249, 251,253, 255, 257, 259 during expansion and compression of the expansiblesupport structure 261. Also during expansion, the angle of theconnectors 285 relative to the closed cells may change. Placing theloops 249, 251, 253, 255, 257, 259 on closed cells separated by oneclosed cell may keep the guidewire lumens 243, 245, 247 from twisting.As the expansible support structure 261 expands, the guidewire lumens243, 245, 247 may diverge into predetermined positions. The expandedcatheter apparatus 241 may not block the vasculature.

Upon completion of a procedure, the expansible support structure 261 maybe compressed and withdrawn from the vasculature. The sheath 265 may beslid distally over the expansible support structure 261. Preferably, noparts of the catheter apparatus 241 extend outside of the cylindricalplane of the compressed expansible support structure 261 in thecompressed state to facilitate withdrawal of the catheter apparatus 241.

FIG. 13 shows another loop embodiment of an expansible structure 295. Incontrast to the loop embodiment 241 of FIGS. 12A-12C, the loopembodiment of the expansible structure 295 of FIG. 13 may have loops297, 299, 301, 303, 305, 307 attached on any of closed cell 309, 311,313, 315. The operation of the apparatus of the loop embodiment of theexpansible structure 295 is similar to the operation of the loopembodiment 241 of FIGS. 12A-12C.

To prevent twisting and damage to guidewire lumens 243, 245, 247,connecting members 317 may couple connection points 319 of struts 321 ona closed cell, such as 309, to connection points 323 of struts 321 on anadjacent closed cell, such as 311. The connection points 319, 323 arepreferably both distal or both proximal relative to the distal end ofthe catheter apparatus 295. The number and configuration of theconnecting members 317 may be variable. The connecting members 317 mayhave an upward bend 325 and a downward bend 327. The bends 325, 327prevent twisting and damage to the guidewire lumens 243, 245, 247 duringexpansion and contraction of the expansible structure 295. Duringexpansion and contraction of the expansible structure 295, the upwardbend 325 and the downward bend 327 cancel and lateral movement of theloops 297, 299, 301, 303, 305, 307.

The connecting members 317 of the expansible structure 295 may allowloops on each closed cell 309, 311, 313, 315. Loops 297, 299, 301, 303,305, 307 do not need to be on every other closed cell 309, 311, 313,315. The embodiment of FIG. 13 may provide for flexibility of theexpansible structure 295 and may facilitate expansion and contractionduring deployment and removal.

The invention also includes embodiments of a catheter apparatus havingtranslating lumens. In particular, one or more smaller lumen catheterspass through the lumen of the catheter apparatus. These lumen catheters,in various quantities, may be individually, jointly, or a combinationthereof movable such that the lumen catheters are capable oftelescoping. For example, the lumen catheters can be advancedindividually or collectively beyond the distal end of the catheterapparatus. The lumen catheters can be advanced and retracted as desiredin an effort to cross a lesion, for example. The lumen catheters areconfigured to allow passage of one or more guidewires. Any of the lumensof any of the catheter embodiments above may be configured to allowpassage of these lumen catheters. Thus, the translating lumen cathetersmay be used in any of the embodiments described above.

The lumen catheters may be shafts configured for passing over theguidewire. In certain embodiments, the lumen catheters may beconstructed as shafts with either a circular, oval, or rectangularshape. Other shapes are possible depending on particular uses.Furthermore, each lumen catheter may be individually movable andadvanceable beyond the distal end of the catheter apparatus as well asretractable into the catheter apparatus. The lumen catheters may becapable of extending beyond the distal end of the catheter apparatus andretracting into the catheter apparatus. Each of the lumen catheters maybe capable of being advanceable and retractable, for example,approximately 1 to 3 inches, beyond the distal end of the shaft of thecatheter apparatus. In one embodiment, an actuator may control movementof the one or more lumen catheters.

This embodiment may include a catheter apparatus including an outershaft (such as a sheath) having a lumen, a main catheter shaft having alumen, one or more lumen catheters configured for passing over one ormore guidewires and a scaffold structure whereby the scaffold structureis attached to the inner shaft, and whereby the inner shaft and one ormore lumen catheters telescope independently of each other. The scaffoldmay be configured to be non-occluding, allowing blood to flow through.Features of the present invention also include expansion or activationof a distal tip for creating a scaffold structure. In certainembodiments, the outer shaft (e.g. sheath), main catheter shaft andlumen catheters may be slideably operable independently of each other.

The lumen catheters may advance and/or retract in any combination ofpatterns and/or in unison. The movement may be controlled on anindividual lumen catheter basis or movement relative to other, one ormore of the other lumen catheters and/or the catheter. Thus, the lumencatheters may be used to attack an occlusion at more than one position.For example, in one embodiment, two lumen catheters may be individuallyadvanced to attack an occlusion at two different positions.

FIG. 14A-D show catheter 335 having lumen catheters 337, 339 and 341 andits operation. The lumen catheters 337, 339 and 341 pass through one ormore lumens in catheter 335. The lumen catheters 337, 339 and 341 may bemovable. Thus, lumen catheters 337, 339 and 341 may be capable ofadvancing beyond the distal end of the catheter apparatus and capable ofretracting into the catheter apparatus. The lumen catheters may beindividually or jointly movable. The lumen catheters may also beoperably linked to an actuator. Operation of the actuator may result inadvancement/retraction of one or more lumen catheters. The actuator maybe configured so that in mode one more the lumens move jointly and whilemoving individually (separately) in another mode. In certainembodiments, the lumen catheters may be directly attached to theactuator.

FIG. 14A shows the lumen catheters 337, 339 and 341 in their unextendedposition inside the distal end of catheter 335. In that position, thedistal end of the lumen catheters 337, 339 and 341 is approximatelyflush with the distal end of catheter 335. Catheter 335 may beconfigured to be a hollow tube. Alternatively, catheter 335 may be asolid tube with a lumen for each lumen catheter 337, 339, and 341. Thelumens may be distributed approximately equidistant from each other.FIG. 14B shows the telescoping of lumen catheter 337. As shown in FIG.14B, lumen catheter 337 advances from the distal end of catheter 335.Lumen catheters 339 and 341 may remain in their retracted position orthey may telescope jointly or individually. FIG. 14C shows lumencatheter 341 in its extended position. In certain embodiments, lumencatheter 341 may extend between about 1 and about 3 inches beyond thedistal end of the catheter 335. FIG. 14D shows lumen catheters 337, 339,and 341 in their extended position telescoping from the distal end ofthe catheter 335. The lumen catheters 337, 339 and 341 may be configuredto allow passage of one or more guidewire through each lumen catheter.

FIG. 14E illustrates operation a catheter apparatus 335 with lumencatheters 337 and 339. The lumen catheters 337 and 339 may be jointly orseparately movable. An actuator (not shown) may control movement of thelumen catheters 337 and 339. The lumen catheters 337 and 339 areconfigured for passage of one or more guidewires. While only two lumencatheters are shown, it should be understood that the number of lumencatheters may vary. The lumen catheters have a lumen therethrough. Aguidewire, such as guidewire 340, may pass through the lumen of thelumen catheter.

Step 1 of FIG. 14E shows the catheter apparatus 335 in an initial statewith optional retractable outside sheath 336 covering the distal end ofthe catheter apparatus 335. It should be understood that in alternateembodiments, catheter 335 does not have outside sheath 336. The distalend of the catheter apparatus 335 may be exposed by withdrawing theretracting sheath from the distal end of the catheter apparatus as shownin Step 2. As the catheter apparatus is positioned, lumen catheter 337and 339 are individually advanced and guidewires 338 and 340 may beadvanced beyond the distal end of the lumen catheters. The one or morelumen catheters 337 and 339 may then assume a final spaced or relaxedconfiguration. The one or more lumen catheters 337 and 339 may moveoutward relative to one another a desired distance and/or into contactwith inner walls of a vasculature with an occlusion 340. The lumencatheters 337 and 339 may assume a final spaced or relaxed configurationas shown in Step 7. As shown in steps 2 to 7, the guidewires are stillinside the lumen catheter 337 and 339. A guidewire 340 may then bethreaded through the one or more lumen catheters (e.g. lumen catheter339) as shown in Step 8 to pass through occlusion 342. After completionof a procedure, the retracting sheath 336 may be advanced towards thedistal end of the catheter apparatus to compress the one or moreguidewire lumen catheters 337 and 339 into a compact arrangement forremoval from the vasculature. Alternatively, the one or more lumencatheters 337 and 339 may be withdrawn into the distal end of theretracting sheath 336 before removal from the vasculature.

The guidewires can be advanced regardless of the position of the lumencatheters. The guidewires 338 and 340 of the catheter apparatus may bemoved into closer contact with the occlusion 342. In one embodiment, theguidewires are advanced when the one or more lumen catheters 337 and 339assume a final spaced or relaxed configuration. The guidewires 338 and340 may move outward relative to one another a desired distance and/orinto contact with inner walls of a vasculature with an occlusion 340. Inone embodiment, the guidewires 338 and 340 may be advanced before theone or more lumen catheters 337 and 339 are in contact with avasculature. In another embodiment, the guidewires 338 and 340 may notbe advanced until the one or more lumen catheters 337 and 339 are incontact with a vasculature.

The lumen catheters 337, 339 and 341 may be surrounded by an expandablesupport structure. In one embodiment, a single expandable supportstructure may surround all of the lumen catheters. One or moreexpandable support structures are contemplated. Thus, in certainembodiment, each of the lumen catheters may be surrounded by anexpandable support structure that only surrounds that lumen catheter.

The expansible support structure may be attached to one or more of thelumen catheters such that advancement of the lumen catheters results inexpansion of the expansible support structure. Any of the expansiblesupport structures described herein (such as e.g. scaffolds) may beused. The lumen catheters may also be operably linked to an actuator.The actuator may be configured so that in one embodiment one or more thelumens are capable of moving jointly in one mode, capable of movingindividually (separately) in another mode and/or any combination ofindividual and joint movement. In certain embodiments, the lumens may bedirectly attached to an actuator.

FIGS. 15A-C show the distal end of a catheter 343 having lumen catheters345, 347 and 349 and expansible support structure 351. The expansiblesupport structure 351 surrounds the lumen catheters 345, 347, and 349.The expansible support structure may surround all of the lumen catheterstogether. The expansible support structure may be retractable intocatheter 343, as described in more detail above. Alternatively, a sheathas described above may cover the expansible support structure 351. Thecatheter 343 may be a hollow tube, as described in more detail above.Alternatively, catheter 343 may be a solid tube with at least a lumenfor each of the lumen catheters.

FIG. 15A shows the distal end of a catheter 343 (not shown) having lumencatheters 345, 347, 349, and expansible support structure 351 with theexpansible support structure in its expanded state. Any number of lumencatheters may be used. Each lumen catheter 345, 347, and 349 has a lumen354 extending therethrough and the lumen is configured for passing aguidewire. Guidewire 355 is shown passing through lumen catheter 347.The guidewire 355 may also be advanceable through the lumen catheter347. Alternatively, each lumen catheter may have one or more lumenprovided through each lumen catheter. The expansible support structure351 may have one or more loops 353. Each of the lumen catheters may bein held in position by the one or more loops 353. The at least one ofthe one or more loops 353 may be located towards the distal end ofexpansible support structure 351 with a lumen catheter passingtherethough. The lumen catheters 345, 347 and 349 may be individually orjointly moveable. In one embodiment, the lumen catheters 345, 347 and349 may telescope beyond the distal end of the expansible supportstructure 351. The distal end of lumen catheters 345, 347 and 349 maypass through loops 353 on the distal end of expansible support structure351. The distal end of lumen catheter such as e.g. lumen catheter 357may be configured to be advanceable beyond the distal of expansiblesupport structure 351.

FIG. 15B is a distal end view of catheter 343 with lumen catheters 345,347, and 349. Each of the lumen catheters 345, 347, and 349 has one ormore lumens through which guidewires 355 may pass. Expansible supportstructure 351 is shown surrounding lumen catheter 345, 347, and 349. Asshown in FIG. 15C, catheter has one lumen configured for passage of eachof the lumen catheters.

FIG. 15C illustrates the operation of catheter 343 of FIG. 15A and FIG.15B. In particular, this figure illustrates how in certain embodimentsof the invention illustrate how the guidewires advance. This figure alsoillustrates how the telescoping lumen catheters serve to follow theguidewire and may provide support to the guidewire. Similar operationalprocedures may be used for other embodiments described herein. Step 1 ofFIG. 15C shows catheter 343 with optional retractable outside sheath 356(not shown) moved back distally from the catheter 343 such thatexpansible scaffold 351 is partially exposed. Steps 2 to 4 show furtherincremental stages of retraction of the retractable outside sheath 356.As the retractable outside sheath 356 is retracted back over thecatheter 343, the expansible support structure 351, which surroundslumen catheters 345, 347, and 349, is incrementally exposed and allowedto expand. As the expansible support structure 351 expands the lumencatheters 345, 347 and 349 separate and are held in a desired positionby the shape-memory allow materials or by coupling to the expansibleportion 357. Step 4 shows the expansible support structure 351 in afully deployed state. Steps 11 and 12 show lumen catheters 345, 347 and349 with the expansible support structure 351 in a fully deployed state.At any stage of the expansion, the lumen catheters 345, 347 and 349 maybe advanced to telescope beyond the distal end of the expansible supportstructure 351 or retracted. Thus, for example, as shown in Steps 6 to 12of FIG. 15C, lumen catheter 347 may be advanced to telescope beyond thedistal end of expansible support structure 351 or retracted.Furthermore, guidewire 355 may also be advanced to telescope and/orretracted at any stage of the expansion. Thus, as shown in steps 8 to12, guidewire 355 may be advanced beyond the distal end of lumencatheter 347.

In another embodiment of a catheter apparatus according to theinvention, the one or more lumen catheters surround the main cathetershaft rather than passing through a lumen in the main catheter shaft.The scaffold is disposed on or attached to towards the distal of thecatheter shaft. The main catheter shaft may have one or more lumens.Alternatively, the main catheter shaft may not have a lumen. FIG. 16A toC show the distal end of catheter 361 having main catheter shaft 373,expansible scaffold 369 and lumen catheters 363, 365, and 367. Catheter361 may have lumens through which lumen catheters 363, 365, and 367 maypass. Alternatively, catheter 361 may not have a lumen. FIG. 16A showslumen catheters 363, 365, and 367 of catheter 361 (not shown). Thenumber and arrangement of lumen catheters can vary depending on thecontemplated use. Each of the lumen catheters 363, 365 and 367 has alumen through which a guidewire may pass. As shown in FIG. 16A, thelumen catheters 363, 365, and 367 may expand outwardly towards thedistal end. FIG. 16A also shows end views of the distal and proximal endof the lumen catheters 363, 365, and 367 including their lumens. FIG.16B shows expansible scaffold 369 in its expanded state. The scaffold369 is disposed or attached towards the distal end of main cathetershaft 373. The scaffold 369 may be disposed on or attached to the distalend of main catheter shaft. The scaffold 369 includes cells 375 andinward facing loops 371. Each cell is approximately hexagonal and hasexpansible S-shaped (zig-zag) connectors 377 on two opposing sides ofthe hexagon. The configuration and arrangement of each cell, includingthe connectors, may vary. For example, the connectors may beapproximately FIG. 8 shaped. The inward facing loops 371 are configuredfor passing over lumen catheters 363, 365, and 367. FIG. 16B also showsa distal end view of the scaffold 369 with loops 371 visible and aproximal end view the main catheter body. As shown in FIG. 16C, maincatheter shaft 373 may be surrounded by lumen catheters 363, 365 and367. FIG. 16C shows the distal end of catheter 361. The distal end viewshows lumen catheters 363, 365 and 367 passing through inward facingloops of scaffold 369. FIG. 16C also shows the proximal end view ofcatheter 361. In the proximal end view, main catheter body 373 issurrounded by lumen catheters 363, 365, and 367. This embodiment of thedevice can achieve a lower overall profile and greater flexibility thanwhen the scaffold is attached to the catheter. Furthermore, theconfiguration of this device allows for additional space for thetelescoping lumens to move.

FIG. 17A is a perspective view of expansible scaffold 391 in itsexpanded state, which may be used in a catheter apparatus of theinvention. Scaffold 391 includes cells 393. Each cell is approximatelyhexagonal and has expansible S-shaped (zig-zag) connectors 395 on twoopposing sides of the hexagon. In one embodiment, these S-shaped(zig-zag) connectors are approximately parallel to an axis passingthrough the center of the scaffold from the distal to the proximal end.The scaffold also includes inward projecting loops 397. The loops areconfigured for passing a lumen catheter. The number and configuration ofthe loops and cells, including the connectors, may vary. FIG. 17B showsa flat projection of expansible scaffold 391 with hexagonal cells 393,S-shaped (zig-zag) connectors 395 and loops 397.

FIG. 18A to C show another embodiment of a catheter apparatus inaccordance with the invention. Catheter apparatus 399 utilizes scaffold391 described above. As shown in FIG. 18, catheter apparatus 399includes main catheter body 405, scaffold 391 and lumens 407, 409 and411. Lumens 407, 409 and 411 extend through the main catheter bodybeyond the distal end of the catheter body. As discussed above, scaffold391 includes hexagonal cells 393, S-shaped (zig-zag) connectors 395 andloops 397. Lumens 407, 409 and 411 may pass through loops 397. Loops 397of the scaffold 391 may position the lumens 407, 409 and 411 on theinside of the scaffold 391. The catheter apparatus may include sheath401, which has a lumen through which main catheter body 405 may pass.The distal end of sheath 401 may have a two parallel longitudinal axesrunning from opposing sides of the lumen of sheath 401. The closerlongitudinal axis passes through the distal tip of sheath 401 and thefurther longitudinal axis passes through the opposite end of the sheath401. The distal end of the sheath 401 may be tapered towards the closerlongitudinal axis. This configuration aids in tracking of the cathetertip over a guidewire. Alternatively, the distal tip of the sheath 401may be tapered, beveled, round or combinations thereof. The sheath 401may include position detection marker 403 towards the distal end of thesheath. The detection marker 403 may be a radio-opaque marker band. Theproximal end of scaffold 391 is disposed toward or on the distal end ofthe main catheter body 405. The proximal end of the scaffold 391 may bephysically attached to main catheter body 405. The proximal end of thescaffold may be held in place by a biologically acceptable glue or afitting 413. When used as part of the apparatus, fitting 413 slides overthe proximal end of the scaffold and holds it in place. As with theother embodiments, this embodiment of the catheter apparatus may beconfigured to allow passage of translating lumen catheters, which maytelescope.

FIG. 18B shows a cross-sectional view taken at Section A-A in FIG. 18A.This cross section view shows the outer sheath 401 surrounding the maincatheter body 405. Lumens 407, 409 and 411 are also visible. In thecenter of the lumens is a small wire running the length of the catheterbody. This wire prevents the lumen from stretching or compressing whilemaintaining flexibility. In addition, FIG. 18C shows an end view of thedistal end of catheter apparatus 399. The end view shows scaffold 391,lumens 407, 409 and 411 extending beyond main catheter body 405 andpassing through the scaffold 397.

Although the foregoing description is directed to the preferredembodiments of the invention, it is noted that other variations andmodifications will be apparent to those skilled in the art, and may bemade without departing from the spirit or scope of the invention.Moreover, features described in connection with one embodiment of theinvention may be used in conjunction with other embodiments, even if notexplicitly stated above.

1-24. (canceled)
 25. A catheter apparatus comprising: a catheter shafthaving a catheter shaft distal end; and a lumen catheter having a lumencatheter distal end, the lumen catheter having a retracted position andan advanced position, wherein, in the retracted position, the lumencatheter distal end is approximately flush with the catheter shaftdistal end, and wherein, in the advanced position, the lumen catheterdistal end extends beyond the catheter shaft distal end.
 26. Thecatheter apparatus of claim 25, wherein the catheter shaft distal endfurther comprises an expansible support structure, wherein, in theretracted position, the lumen catheter distal end is approximately flushwith a distal end of the expansible support structure, and wherein, inthe advanced position, the lumen catheter distal end extends beyond thedistal end of the expansible support structure.
 27. The catheterapparatus of claim 25, wherein the catheter shaft is a hollow body andlumen catheter extends through the hollow body.
 28. The catheterapparatus of claim 25, wherein the lumen catheter is a plurality oflumen catheters.
 29. The catheter apparatus of claim 28, wherein thecatheter shaft is a solid tube having a lumen for each of the pluralityof lumen catheters.
 30. The catheter apparatus of claim 28, wherein eachof the plurality of lumen catheters is configured to move between theretracted position and the advanced position individually of theremaining lumen catheters.
 31. The catheter apparatus of claim 28,wherein the plurality of lumen catheters move between the retractedposition and the advanced position jointly.
 32. The catheter apparatusof claim 28, wherein the plurality of lumen catheters are distributedapproximately equidistant from each other.
 33. The catheter apparatus ofclaim 25, further comprising an actuator, the actuator configured tocontrol movement of the lumen catheter.
 34. The catheter apparatus ofclaim 25, further comprising a sheath, the sheath configured to retractalong the catheter shaft thus allowing the lumen catheter to move fromthe retracted position to the advanced position.
 35. The catheterapparatus of claim 34, wherein the sheath is further configured toadvance along the catheter shaft thus allowing the lumen catheter tomove from the advanced position to the retracted position.